System and method for imaging during a medical procedure

ABSTRACT

In one embodiment, an apparatus may include an imager configured to generate a plurality of frames at a frame frequency greater than an electromagnetic energy emission pulse frequency of a medical device, wherein each frame of the plurality of frames may include a first plurality of rows. The apparatus may also include an electronic shutter module configured to offset a start time of each row of the first plurality of rows in each frame from the plurality of frames from a start time of an adjacent row in that same frame. The apparatus may further include an image processing module configured to generate a plurality of valid frames based on at least a portion of the plurality of frames, wherein the plurality of valid frames may include a frame frequency lower than the frame frequency of the plurality of frames.

CROSS REFERENCE TO RELATED APPLICATION

This patent application claims the benefit of priority under 35 U.S.C.§§119 and 120 to U.S. Provisional Patent Application No. 61/247,008,filed Sep. 30, 2009, which is herein incorporated by reference in itsentirety.

FIELD OF THE DISCLOSURE

Embodiments of the invention relate generally to medical devices andmore particularly to imaging devices and methods for using such devices.

BACKGROUND OF THE DISCLOSURE

By using an imaging system to monitor a medical procedure, a medicalpractitioner can more accurately determine and control the progress ofthe procedure through visual inspection of the area of treatment. Innon-invasive procedures, for example, an imaging endoscope enables themedical practitioner to examine the area of treatment while the medicalprocedure is in progress. For instance, during lithotripsy, anon-invasive procedure for the treatment of stones that typically formin the kidney, bladder, ureters, or gallbladder, a medical device (e.g.,a lithotriptor) is used to provide pulses of focused, high-intensityshock waves (e.g., pressure waves) and/or electromagnetic radiation(e.g., laser) to break up the stones. By using an imaging endoscopewithin the medical device, a medical practitioner can locate the stonesand aim or target the treatment effectively at the place where thestones are located. Moreover, the medical practitioner can monitor theprogress of the stone fragmentation and adjust the procedure (e.g.,intensity, frequency) accordingly.

The intense pulses produced by the medical device, however, can affectthe operation of an imaging sensor in the imaging endoscope. Forexample, when sufficient back-scattered energy (e.g., electromagneticradiation) strikes the imaging sensor during treatment, the timing ofcertain circuitry within the imaging sensor can be disrupted, affectingthe quality of the video output. Moreover, back-scattered energy cansaturate many of the sensing elements (e.g., pixels) in the imagingsensor, which also affects the quality of the video output. A reducedvideo output quality can limit the ability of the medical practitionerto effectively locate and/or treat the stones.

Thus, a need exists for an imaging system that can be used in medicalprocedures and that reduces and/or offsets the effects of energy pulseson the quality of the video output.

SUMMARY OF THE DISCLOSURE

One exemplary aspect of the present disclosure is directed to anapparatus. The apparatus may include an imager configured to generate aplurality of frames at a frame frequency greater than an electromagneticenergy emission pulse frequency of a medical device, wherein each frameof the plurality of frames may include a first plurality of rows. Theapparatus may also include an electronic shutter module configured tooffset a start time of each row of the first plurality of rows in eachframe from the plurality of frames from a start time of an adjacent rowin that same frame. The apparatus may further include an imageprocessing module configured to generate a plurality of valid framesbased on at least a portion of the plurality of frames, wherein theplurality of valid frames may include a frame frequency lower than theframe frequency of the plurality of frames.

Various embodiments of the disclosure may include one or more of thefollowing aspects: the electronic shutter module may terminate a currentframe from the plurality of frames in response to at least one of asynchronization pulse from the medical device and an electromagneticenergy associated with the medical device; the imager may be asolid-state imager having an addressable pixel array including a secondplurality of rows, each row of the second plurality of rows may beassociated with a row from the first plurality of rows in a frame fromthe plurality of frames; a valid portion of a frame from the pluralityof frames may include at least one valid row and may be included in avalid frame from the plurality of valid frames; the image processingmodule may include a temporal filter configured to combine a validportion of at least two adjacent frames from the plurality of frames toproduce a valid frame from the plurality of valid frames; the imager maybe configured to read out an initial frame from the plurality of framesin response to at least one of a power-on reset being complete and asynchronization signal from the medical device; a first frame from theplurality of frames may be before a second frame from the plurality offrames, and wherein the electronic shutter module may be configured toreset to a start of the second frame after the first frame is terminatedin response to at least one of a synchronization pulse from the medicaldevice and an electromagnetic energy associated with the medical device;a valid frame from the plurality of valid frames may include at leastone valid row, the at least one valid row may have a number of validpixels above a predetermined threshold number; a first frame from theplurality of frames may be before a second frame from the plurality offrames, and wherein the image processing module may be configured toreplace an invalid portion of the second frame with an associated validportion from the first frame; the image processing module may include abuffer configured to store a valid portion of at least one frame fromthe plurality of frames; the image processing module may be configuredto adjust an illumination value associated with a pixel in a valid framefrom the plurality of valid frames based on at least one of a darkreference pixel information received from the imager and a calibrationinformation stored in the image processing module; the image processingmodule may include a temporal low-pass filter module configured toproduce an output based on a dark reference pixel information receivedfrom the imager, and wherein the image processing module may beconfigured to adjust an illumination value associated with a pixel in avalid frame from the plurality of valid frames based on the output fromthe temporal low-pass filter; the image processing module may include afast-settling filter module configured to produce an output based on adark reference pixel information received from the imager, wherein thefast-settling filter module may be actuated in response to at least oneof a synchronization pulse from the medical device and anelectromagnetic energy associated with the medical device, and whereinthe image processing module may be configured to adjust an illuminationvalue associated with a pixel in a valid frame from the plurality ofvalid frames based on the output from the fast-settling filter; and theapparatus may include an endoscope.

Another exemplary aspect of the present disclosure is directed to amethod. The method may include defining a plurality of video frames atan imager based on a received electromagnetic energy, wherein the imagermay be operatively coupled to an image processing module. The method mayalso include determining whether a row in a video frame from theplurality of video frames is an invalid row in response to the receivedelectromagnetic energy, wherein a first video frame from the pluralityof video frames may be before a second video frame from the plurality ofvideo frames. The method may further include replacing at least oneinvalid row in the second video frame with an associated valid row fromthe first video frame to produce a first valid video frame. The methodadditionally may include generating a plurality of valid video frames,wherein the plurality of valid video frames may include a framefrequency lower than a frame frequency of the plurality of video frames.

Various embodiments of the disclosure may include one or more of thefollowing aspects: generating the plurality of video frames at a firstfrequency, the first frequency being greater than an electromagneticenergy emission pulse frequency of a medical device; a row in the secondvideo frame may be invalid when an associated row in the first videoframe is invalid and a number of valid pixels in the row in the secondvideo frame may be below a predetermined threshold number; and deemingan invalid row to be a valid row after the invalid row has been replacedin a predetermined number of consecutive video frames from the pluralityof video frames.

Yet another exemplary aspect of the present disclosure is directed toanother method. The method may include inserting an imager into a bodyof a patient, activating a medical device to transmit an electromagneticenergy to the body of the patient, and generating a plurality of framesat a frame frequency greater than an electromagnetic energy emissionpulse frequency of the medical device, wherein the imager may beconfigured to terminate at least a frame from the plurality of frames inresponse to at least one of a synchronization pulse from the medicaldevice and an electromagnetic energy associated with the medical device.The method may also include offsetting a start time of each row in eachframe from the plurality of frames from a start time of an adjacent rowin that same frame.

Various embodiments of the disclosure may include one or more of thefollowing aspects: adjusting a power level of the electromagnetic energytransmitted to the body of the patient from the medical device;adjusting the frame frequency of the plurality of frames; determiningwhether a frame from the plurality of frames is a first valid frame; andgenerating a plurality of valid frames including the first valid frame,the plurality of valid frames having a frame frequency lower than aframe frequency of the plurality of frames.

In this respect, before explaining at least one embodiment of thepresent disclosure in detail, it is to be understood that the presentdisclosure is not limited in its application to the details ofconstruction and to the arrangements of the components set forth in thefollowing description or illustrated in the drawings. The presentdisclosure is capable of embodiments in addition to those described andof being practiced and carried out in various ways. Also, it is to beunderstood that the phraseology and terminology employed herein, as wellas the abstract, are for the purpose of description and should not beregarded as limiting.

The accompanying drawings illustrate certain exemplary embodiments ofthe present disclosure, and together with the description, serve toexplain the principles of the present disclosure.

As such, those skilled in the art will appreciate that the conceptionupon which this disclosure is based may readily be used as a basis fordesigning other structures, methods, and systems for carrying out theseveral purposes of the present disclosure. It is important, therefore,to recognize that the claims should be regarded as including suchequivalent constructions insofar as they do not depart from the spiritand scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a medical device and imaging device with aurinary system, according to an embodiment;

FIG. 2 is a schematic block diagram of an imaging system, according toan embodiment;

FIG. 3 is a schematic block diagram of an image processing module and animaging device, according to an embodiment;

FIG. 4 is a schematic block diagram of an imaging device, according toan embodiment;

FIG. 5A is a timing diagram illustrating frame resetting on an imagingdevice resulting from the operation of a medical device;

FIG. 5B is a timing diagram illustrating an increased number of validrows when an imaging device is operated at twice the frequency ofoperation of a medical device, according to an embodiment;

FIG. 6A is a timing diagram illustrating rows with saturated pixels onan imaging device resulting from the operation of a medical device,according to an embodiment;

FIG. 6B is a timing diagram illustrating an increased number of validrows when an imaging device is operated at twice the frequency ofoperation of a medical device, according to an embodiment;

FIG. 7 is a schematic block diagram of a module configured to replaceinvalid rows, according to an embodiment;

FIG. 8 is a schematic block diagram of a module configured to compensatefor changes in pixel offset, according to an embodiment;

FIG. 9 is a schematic block diagram of a module configured to replaceinvalid rows and to compensate for changes in pixel offset, according toan embodiment;

FIG. 10 is a schematic block diagram of a module configured tocompensate for changes in pixel offset, according to another embodiment;

FIG. 11 is a flow chart illustrating a method for replacing invalidrows, according to an embodiment; and

FIG. 12 is a flow chart illustrating a method forming an imaging deviceproximate to a medical device, according to an embodiment.

DETAILED DESCRIPTION

The devices and methods described herein are generally related to theuse of an imaging system (e.g., imaging endoscope) within the body of apatient. For example, the devices and methods are suitable for use in amedical procedure such as lithotripsy, which is a non-invasive procedurefor the treatment of kidney stones (i.e., urinary calculi) and stones ofthe gallbladder or the liver (i.e., biliary calculi). Lithotripsy istypically performed to remove the stones, prevent infection, and/orreduce the likelihood of recurrence in the patient. A lithotriptor is amedical device used during lithotripsy to break up the stones by usingfocused, high-intensity pressure (e.g., acoustic) or electromagneticradiation (e.g., laser) pulses that minimize collateral tissue damage.The imaging system can be used to locate the stone and to appropriatelytarget the treatment such that the pulses are aimed at the place wherethe stone is located. The treatment typically starts at a low powerlevel, with long gaps between pulses to get the patient used to thesensation associated with the treatment. The frequency of the pulses andthe power level can be gradually increased when appropriate to break upthe stone more effectively. The stones break up into smaller pieces byshearing forces and/or cavitation bubbles surrounding the stone producedby the pressure and/or radiation pulses. The smaller pieces can beremoved (e.g., via an endoscope) or can be passed through the patient'surinary system or through a cystic duct, for example. In someembodiments, the pulse frequency can be referred to as an energyfrequency or as an electromagnetic energy emission frequency if thepulse frequency is related to the transmission (e.g., emission) ofelectromagnetic radiation.

Different types of lithotripsy procedures are available, includingultrasonic lithotripsy, extra corporal shock wave lithotripsy (ESWL),electrohydraulic lithotripsy (EHL), and urethroscopic stone removal, forexample. Selection of anyone of these lithotripsy procedures can dependon the type, size, number, and location of the stones, and/or on thecondition of the patient. During ultrasonic lithotripsy, high-frequencysound waves are sent to the stone through an electronic probe insertedinto the ureter. The stone fragments are typically passed by the patientor are removed surgically. In ESWL, pressure waves are sent from outsidethe patient's body and are highly focused on the stones to fragment thestones until they are reduced to small pieces or granules that can bepassed in the patient's urine. For larger stones, multiple ESWLtreatments may be required to reduce the stone to granules of anappropriate size. During EHL, a flexible probe is used to generate shockwaves from an electrical source. The probe is positioned close to thestone through a flexible endoscope (e.g., a urethroscope). The shockwaves are used to reduce the stone to small fragments that can beextracted using the endoscope or that can be passed by the patient.Urethroscopic stone removal is typically used to treat stones located inthe middle and lower ureter. In this procedure, a urethroscope is passedthrough the urethra and bladder and into the ureter. Smaller stones arephysically removed while larger stones are fragmented usingelectromagnetic radiation (e.g., laser).

An imaging system as described herein can be used to produce a videooutput that can assist a medical practitioner in performing and/ormonitoring a medical procedure such as lithotripsy, for example. In thisregard, the video output from the imaging system can allow the medicalpractitioner to locate stones, focus the shock waves or laser radiationat the precise place where the stones are located, and/or monitor thefragmentation and/or removal of the stones. The medical practitioner canadjust the target location of the lithotriptor pulses, the power levelof the lithotriptor pulses, and/or the frequency of the lithotriptorpulses in accordance with the real-time feedback provided by the videooutput. The imaging system can include an imaging device or sensor andan image processing module. An electrical conduit can be used to connectthe imaging device and the image processing module. One end of theelectrical conduit can be coupled to the image processing module whilethe other end of the electrical conduit, the distal end portion, can becoupled to the imaging device and can be inserted into the patient'sbody.

It is noted that, as used in this written description and the appendedclaims, the singular forms “a,” “an,” and “the” include plural referentsunless the context clearly dictates otherwise. Thus, for example, theterm “a wavelength” is intended to mean a single wavelength or acombination of wavelengths. Furthermore, the words “proximal” and“distal” refer to direction closer to and away from, respectively, anoperator (e.g., medical practitioner, medical practitioner, nurse,technician, etc.) who would insert the medical device into the patient,with the tip-end (i.e., distal end) of the device inserted inside apatient's body. Thus, for example, the end inserted inside a patient'sbody would be the distal end of an endoscope, while the end outside apatient's body would be the proximal end of the endoscope.

FIG. 1 is an illustration of a medical device and imaging device with aurinary system 10, according to an embodiment. The urinary system 10 hasa urethra 2, a bladder 4, two ureters 6 and 8, and two kidneys 11 and12. The kidneys 11 and 12 are bean-shaped organs that remove urea fromthe blood and produce mine from the urea, water, and other wastesubstances. Urine travels from the kidneys 11 and 12 down to the bladder4 via the ureters 6 and 8, respectively. Each of the ureters 6 and 8 isa narrow conduit, typically about 8 to 10 inches in length. Muscles inthe ureter walls regularly tighten and relax to force urine away fromthe kidneys 11 and 12 and into the bladder 4. The bladder 4 is aballoon-shaped hollow organ that stores the urine until the body isready to empty the urine through the urethra 2.

Stones are typically formed in the kidney. The stones can remain in thekidney or can travel and be found anywhere in the urinary system 10. Forexample, stones can travel down from the kidney 11 to the ureter 6,which can result in a blockage at the ureter 6 that reduces or preventsthe passage of urine from the kidney 11 to the bladder 4. If urine doesnot properly flow from the kidney 11 to the bladder 4 (e.g., standsstill or backs up), a kidney infection can develop. In this regard, amedical procedure, such as lithotripsy, can be used to remove the stonefrom the ureter 6 and prevent further injury or illness to the patient.

FIG. 1 also shows an expanded view A of an inner portion of the uterer 6that illustrates a medical device (e.g., a lithotripsy device) andimaging device associated with the presence of a stone 120 lodged withinthe ureter 6. During a urethroscopic stone removal procedure to removethe stone 120, for example, a medical device 124 and an endoscope 125are passed through the urethra 2 and the bladder 4 and are positionedwithin the ureter 6 near the stone 120. The endoscope 125 includes aconduit 130 and a conduit distal end portion 126 having an imagingdevice or sensor 128. The medical device 124 includes a distal endportion 122 configured to produce an output EM1 having one or morepulses of electromagnetic radiation (e.g., laser radiation) and/orsynchronization pulses. The output EM1 can be associated with multiplewavelengths (e.g., optical wavelengths), multiple power levels, and/ormultiple pulse frequencies. In some embodiments, the pulses ofelectromagnetic radiation and/or synchronization pulses associated withthe output EM1 can be generated by an electromagnetic radiation emissionsource (e.g., a laser source) (not shown) coupled to the distal endportion 122 of the medical device 124 via an optical fiber (not shown),for example. In some embodiments, one or more components and/orfunctions of the medical device 124 can be associated with (e.g.,coupled to, included in) the endoscope 125 (or other imaging system thatincludes in the endoscope 125), or vice versa. For example, theelectromagnetic radiation emission source (and/or one or more functionsof the electromagnetic radiation source) can be coupled to or includedin the endoscope 125.

The endoscope 125 enables the medical practitioner to position theimaging device 128 in the conduit distal end portion 126 near the areaof treatment (i.e., the location of the stone 120) such that the medicalpractitioner can locate the stone 120 and/or to monitor the medicalprocedure. In some embodiments, the conduit distal end portion 126 canhave an illumination device (not shown), such as a light emitting diode(LED), for example, to illuminate the area of treatment and provide abetter video output for use by the medical practitioner. Once the areaof treatment is located, the medical device 124 can be appropriatelyaimed at the area of treatment and the medical practitioner can adjustthe power level and/or pulse frequency associated with the output EM1 toeffectively fragment the stone 120. In some embodiments, the fragmentsof the stone 120 can be extracted using an endoscope (e.g., theendoscope 125) or can be passed by the patient. The endoscope 125 can beused in other medical procedures in addition to the urethroscopic stoneremoval procedure described above.

FIG. 2 is a schematic block diagram of an imaging system 200, accordingto an embodiment. The imaging system 200 includes a control module 210,a connector 222, a conduit 230, and a suitable catheter or endoscope225. The imaging system 200 can be used in connection with a medicalprocedure, such as lithotripsy, for example. The conduit 230 includes aconduit distal end portion 226 having an imaging device or sensor 228.The control module 210 includes an image processing module 220.

The image processing module 220 is configured to process one or moreoutputs (e.g., video outputs) produced by the imaging device 228 andreceived by the control module 210 through the conduit 230. The imageprocessing module 220 can be software-based (e.g., set of instructionsexecutable at a processor, software code) and/or hardware-based (e.g.,circuit system, processor, application-specific integrated circuit(ASIC), field programmable gate array (FPGA)).

In some embodiments, the control module 210 can be configured to providepower and/or control signals to one or more components in the conduitdistal end portion 226 through the conduit 230. For example, the controlmodule 210 can provide power and/or control signals to operate theimaging device 228. In another example, the control module 210 canprovide power and/or control signals to operate an illumination device(not shown) in the conduit distal end portion 226. The control module210 can provide power and/or control signals to one or more componentsin the conduit distal end portion 226 through, for example, the imageprocessing module 220. In some embodiments, the control module 210 caninclude a laser source (not shown), such as a laser diode, for example,configured to produce an electromagnetic radiation output that can becoupled to the conduit distal end portion 226 through the conduit 230.The electromagnetic radiation output produced by the laser source can beemitted from the conduit distal end portion 226 to illuminate the areaof treatment.

In some embodiments, the control module 210 can include additionalcomponents (not shown) configured to provide additional processingcapabilities. For example, the control module 210 can include one ormore modules configured to perform color processing operations. Inanother example, the control module 210 can include one or more modulesconfigured to perform video encoding or compression operations. Inanother example, the control module 210 can include one or more modulesconfigured to format video into one or more recording formats and/orvideo transmission formats such as the National Television SystemCommittee (NTSC), high-definition video formats, and standard-definitionvideo formats. In some embodiments, at least some of the additionalprocessing capabilities described above with respect to the controlmodule 210 can be performed by the image processing module 220.

The conduit 230 is coupled to the control module 210 through theconnector 222. The proximal end portion of the conduit 230 is configuredto receive power and/or control signals from the control module 210 andthe distal end portion of the conduit 230 is configured to receive atleast a video output from the imaging device 228 in the conduit distalend portion 226. The conduit 230 can include, for example, one or moreelectrically conductive wires, one or more optical fibers, and/or one ormore coaxial cables. The conduit 230 includes an elongate portion thatcan be flexible to allow the elongate portion to be maneuvered withinthe endoscope 225, for example.

The endoscope 225 can define one or more lumens. In some embodiments,the endoscope 225 includes a single lumen that can receive therethroughvarious components such as the conduit 230. The endoscope 225 has aproximal end configured to receive the conduit distal end portion 226and a distal end configured to be inserted into a patient's body forpositioning the conduit distal end portion 226 in an appropriatelocation for a medical procedure. For example, during a lithotripsyprocedure to remove stones in the urinary system 10 described above withrespect to FIG. 1, the endoscope 225 can be used to place the conduitdistal end portion 226 at or near the stone 120. The endoscope 225includes an elongate portion that can be flexible to allow the elongateportion to be maneuvered within the body (e.g., urinary system 10). Theendoscope 225 can also be configured to receive various medical devicesor tools through one or more lumens of the endoscope, such as, forexample, irrigation and/or suction devices, forceps, drills, snares,needles, etc. An example of such an endoscope with multiple lumens isdescribed in U.S. Pat. No. 6,296,608 to Daniels et al., the disclosureof which is incorporated herein by reference in its entirety. In someembodiments, a fluid channel (not shown) is defined by the endoscope 225and coupled at a proximal end to a fluid source (not shown). The fluidchannel can be used to irrigate an interior of the patient's body duringa medical procedure. In some embodiments, a different channel (notshown) is defined by the endoscope 225 and coupled at the proximal endto a suction source (not shown). The channel can be used to remove stonefragments that result from lithotripsy, for example.

FIG. 3 is a schematic block diagram of an image processing module 320and an imaging device 328, according to an embodiment. The imageprocessing module 320 and/or the imaging device 328 can be used in theimaging system 200 described above with respect to FIG. 2. The imageprocessing module 320 is configured to perform various video processingoperations including, for example, adjusting, replacing, and/ormodifying invalid portions of one or more video frames received from avideo output produced by the imaging device 328. In some embodiments,the imagining device 328 can be referred to as an imager. The imageprocessing module 320 is configured to adjust and/or modify a rate orfrequency associated with the video frames processed by the imageprocessing module 320. The functionality provided by the imageprocessing module 320 can be software-based (e.g., set of instructionsexecutable at a processor, software code) and/or hardware-based (e.g.,circuit system, processor, application-specific integrated circuit(ASIC), field programmable gate array (FPGA)). In some embodiments, theimage processing module 320, when associated with (e.g., coupled to,included in) an endoscope such as that shown in FIG. 2, can be referredto as an endoscopic image processing module. In some embodiments, theimage device 328, when associated with (e.g., coupled to, included in)an endoscope such as that shown in FIG. 2, can be referred to as anendoscopic imager.

The image processing module 320 is configured to receive an input I32that includes one or more signals to control the operation of the imageprocessing module 320. The control signals associated with the input I32can result from the operation of other components or modules in thecontrol module 210 described above with respect to FIG. 2. For example,one or more control signals associated with the input I32 can bereceived from components or modules in the control module 210 inresponse to input received from a user (e.g., medical practitioner) inconnection with a medical procedure. The input I32 includes one or moresignals to control the adjustment, replacement (e.g., replacementtiming), and/or modification of invalid portions of one or more videoframes to be processed by the image processing module 320. The input I32can include, for example, one or more signals to control a rate orfrequency associated with video frames processed by the image processingmodule 320.

The input I32 can also include one or more signals that can be used bythe image processing module 320 to control the operation of the imagingdevice 328. For example, the input I32 can include one or more signalsthat can be used by the image processing module 320 to control the rateor frequency associated with the video output of the imaging device 328.In this regard, the image processing module 320 is configured to producean output O31 that includes one or more signals to control the operationof the imaging device 328. In some instances, the image processingmodule 320 can be configured to be a source of power (e.g., DC voltage)to the imaging device 328 via the output O31, or via a different output(not shown).

The imaging device 328 can be a complementary metal-oxide-semiconductor(CMOS) image sensor, a charge-coupled-device (CCD) image sensor, aninfrared (IR) image sensor, a micro-electro-mechanical (MEM) array, or afocal plane array, for example. In one embodiment, the imaging device328 is configured to receive electromagnetic radiation in the visiblerange (e.g., between about 400 nm and 800 nm) and/or near infrared range(e.g., between about 800 nm and 1200 nm) associated with a particularfield of view (e.g., area of treatment). The imaging device 328 isconfigured produce one or more video frames, each video framerepresentative of a scene and a time associated with the field of viewfrom which the electromagnetic radiation was received and based on thereceived electromagnetic radiation.

The image processing module 320 is configured to receive an input I34from the imaging device 328 that includes one or more video frames(i.e., the video output). The video frames in the input I34 areprocessed by the image processing module 320. The image processingmodule 320 can be configured to operate with more than one type ofimaging device 328 such as imaging devices having different resolutionsand/or configured to capture a different spectrum of electromagneticradiation.

The image processing module 320 is configured to produce an output O33having a video stream that includes multiple frames processed by theimage processing module 320. In some embodiments, the output O33 can besent to another component or portion of the proximal end portion 210described above with respect to FIG. 2, for example, for furtherprocessing (e.g., post-processing). The output O33 can includeinformation related to the configuration and/or operation of the imageprocessing module 320 and/or of the imaging device 328.

FIG. 4 is a system block diagram of an imaging device 428, according toan embodiment. The imaging device 428 includes a column select module410, a row select module 420, an pixel array 430, a controller module440, and an input/output (I/O) module 460. Optionally, the imagingdevice 428 can include an analog-to-digital converter (ADC) module 470and/or a processing module 480. The controller module 440 includes anelectronic shutter module 450. The functionality provided by the imagingdevice 428 is hardware-based or hardware-based and software-based.

The pixel array 430 includes multiple picture elements (i.e. pixels) 431arranged in one or more columns and rows. For example, the pixel array430 can have a Video Graphics Array (VGA) size or resolution thattypically includes 640 columns by 480 rows of pixels 431. In otherembodiments, the pixel array 430 can have an array size smaller than aVGA-sized array or can have an array size larger than a VGA-sized array.For example, the pixel array 430 can have a super VGA (SVGA) size thattypically includes 800 columns by 600 rows of pixels 431. In anotherexample, the pixel array 430 can have more than one million pixels 431(e.g., megapixel array) arranged in multiple configurations of columnsand rows. In some embodiments, the size of the pixel array 430 can becustomized for a particular application (e.g., a particular medicalprocedure). In this regard, the size of the pixel array 430 may dependon a desirable resolution that is suitable for assisting a medicalpractitioner during a particular medical procedure.

Each pixel 431 in the pixel array 430 is configured to receiveelectromagnetic radiation (not shown) and convert the receivedelectromagnetic radiation to an associated electrical charge or voltage(not shown). Pixels in the pixel array 430 can have an optical filter(not shown) to filter out or reflect portions of the electromagneticspectrum incident upon the pixel such that the pixel produces anelectrical charge associated only with the portion of theelectromagnetic spectrum that passes through the optical filter. Byusing optical filters of different spectral characteristics throughoutthe pixel array 430 (e.g., repeated color filter mosaic pattern), theimaging device 428 can produce a video output having color information.

The pixel array 430 can include multiple dark (reference) pixels 432associated with one or more columns and/or rows. The dark pixels 432 arecovered (e.g., metal layer) such that electromagnetic radiation incidentupon the dark pixels 432 is substantially reflected. The dark pixels 432are configured to produce DC voltages and/or charges associated withcertain operations of the pixel array 430 such that the DC voltagesand/or charges produced by the dark pixels 432 can be used to offsetand/or compensate for certain DC voltages and/or charges produced bypixels 431 during operation of the imaging device 428. In someembodiments, the information associated with the dark pixels 432 candetermined the operation of the imaging device 428, during amanufacturing calibration operation, and/or during a post-manufacturingsystem calibration operation, for example. The information associatedwith the dark pixels 432 can be stored in the I/O module 460, theprocessing module 480, and/or in a buffer (not shown) or memory (notshown) in the imaging device 428. The dark pixels 432 can be located onthe sides of the pixel array 430.

The I/O module 460 is configured to receive an input I4 from, forexample, a given image processing module such as the image processingmodule 320 described above with respect to FIG. 3. The input I4 includesone or more signals and/or pulses associated with the operation of theimaging device 428. For example, the input I4 can include signals and/orpulses associated with the timing and/or frequency of operation of theimaging device 428 such as a clock signal, a trigger, a frequencycontrol signal, a synchronization signal, a shutter control signal,and/or a reset. The I/O module 460 is configured to communicate or sendsignals and/or pulses received via the input I4 to one or morecomponents of the imaging device 428.

In some embodiments, the input I4 can include signals and/or pulses(e.g., synchronization pulse) associated with the operation of a medicaldevice such as a lithotriptor, for example. When a processing module 480is included in the imaging device 428, the input I4 can include signalsand/or pulses associated with the operation of the processing module480. For example, the input I4 can include signals and/or pulsesassociated with controlling a format of a video output produced by theprocessing module 480.

The I/O module 460 is configured to produce an output O4 that includesone or more signals and/or pulses associated with a video output orvideo stream produced by the imaging device 428. The video output orvideo stream can include one or more video frames and/or portions ofvideo frames. The output O4 can be sent to, for example, a given imageprocessing module such as the image processing module 320 describedabove with respect to FIG. 3. The output O4 can be sent to othercomponents such as video cards (not shown) or frame grabbers (notshown). A video card or a frame grabber is an electronic deviceconfigured to receive an analog video signal or a digital video stream.A frame grabber, for example, can be used in an imaging or vision systemto store, display, and/or transmit video content in raw (i.e.,uncompressed) or compressed digital form.

The controller module 440 is configured to control the operation of atleast some of the components of the imaging device 428. For example, thecontroller module 440 is configured to control timing of operationsassociated with the imaging device 428. In this regard, the electronicshutter module 450 is configured to control timing of operationsassociated with the column select module 410, the row select module 420,and the pixel array 430. For example, the controller module 440 isconfigured to control the time a given pixel 431 is collects a charge orvoltage associated with the intensity and/or spectrum of theelectromagnetic radiation incident on the pixel 431 (i.e., exposure orintegration operation). The controller module 440 is configured tocontrol which rows from the multiple rows in the pixel array 430 are tobe integrated (i.e., collect charges resulting from the incidentelectromagnetic radiation) at a particular time. The charge or voltageassociated with each pixel 431 is transferred to a storage element(e.g., a capacitor) coupled to the pixel to await a readout operation.The controller module 440 is configured to control the readout operationthat follows the exposure or integration operation. In the readoutoperation, the charge or voltage produced by each pixel 431 during theexposure operation is transferred to the ADC module 470 for conversionto a digital value or number (e.g., 8-bit or 10-bit number) or istransferred out of the imaging device 428 via the output O4, forexample.

The electronic shutter module 440 is configured to control operations ofthe imaging device 428 associated with a global shutter or a rollingshutter, for example. When the imaging device 428 is configured tooperate with a global or synchronous shutter, the electronic shuttermodule 440 controls the rows in the pixel array 430 via the row selectmodule 420 such that the pixels in each of the rows are reset (i.e., rowreset) at the same time and are exposed for the same period of time(i.e., integration time). Because the rows are exposed concurrently,using a global shutter typically reduces jagged or blurred effects thatoccur during fast-moving or fast-changing scenes. The charge or voltageassociated with each pixel 431 in a given row is transferred to astorage element (e.g., a capacitor) coupled to the pixel to await thereadout operation. The electronic shutter module 440 controls thereadout of the charge or voltage associated with each pixel 431 in agiven row via the column select module 410. A video frame is built byreading out the exposed rows, one at a time, after the exposureoperation is complete. The time it takes to readout the exposed rowsthat are used to build or compose a video frame can be reflected to asthe readout time. The ADC module 470 and/or the I/O module 460 caninclude a buffer (not shown) or memory (not shown) configured to storeat least a portion of a video frame. Once the rows have been read outand the video frame has been completed, the electronic shutter module440 is configured to reset the pixel array 430 (i.e., frame reset) suchthat a new video frame can be built.

In this regard, the frequency or frame rate associated with the imagingdevice 428 is based at least partly on the time associated with theexposure operation (i.e., integration time) and the time associated withthe readout operation (i.e., readout time). For example, the longer theintegration time and the readout time associated with building a videoframe from multiple exposed rows, the lower the frequency or frame rateat which the imaging device 428 can be operated.

When the imaging device 428 is configured to operate with a rollingshutter, the electronic shutter module 440 controls the rows in thepixel array 430 via the row select module 420 such that each row isreset (i.e., row reset) at a different time and then exposed for aperiod of time (i.e., integration time). For example, each row that isused to build a video frame can be reset or start integrating at a timethat is offset from a rest or start time of an adjacent row in the samevideo frame. In some embodiments, sets of rows can have a reset or starttime that is offset from a reset or start time of an adjacent set ofrows in the same video frame. Because the rows are exposed in an offsetmanner, using a rolling shutter typically produces a uniformly exposedimage even during fast-changing scenes. The charge or voltage associatedwith each pixel 431 in each exposed row is transferred to a storageelement coupled to the pixel to await the readout operation. Theelectronic shutter module 440 controls the readout of the charge orvoltage associated with the pixels 431 in a given row via the columnselect module 410. A video frame is built as each exposed row is readout following completion of the exposure of that row.

In some embodiments, circuitry within the electronic shutter module 450can be affected by, for example, a synchronization pulse or anelectromagnetic radiation (e.g., combustion flash) associated with theoperation of a medical device such as a lithotriptor. The electronicshutter module 450 can disadvantageously reset (i.e., frame reset) froma video frame to a new video frame as a result of the operation of themedical device. Said differently, the electronic shutter module 450 canprematurely terminate a video frame and start a new video frame when asynchronization pulse or an electromagnetic radiation from a medicaldevice occurs. In this regard, the operation of a medical device nearthe imaging device 428 can have an effect on the quality of the videooutput ‘Of the imaging device 428 by disrupting the timing and/orcontrol provided by the electronic shutter module 450, for example.

FIG. 5A is a timing diagram 500 illustrating frame resetting on animaging device that results from the operation of a medical device(e.g., a lithotriptor), according to an embodiment. The timing diagram500 includes a top portion 501 that illustrates periods whensynchronization or electromagnetic radiation pulses are delivered by amedical device such as the medical device 124 described above withrespect to FIG. 1, for example. The timing diagram 500 includes a bottomportion 502 that illustrates multiple video frames associated with avideo output from a given imaging device being used with the medicaldevice in a medical procedure (e.g., a lithotripsy procedure), such asthe imaging devices 228, 238, and 428 described above with respect toFIGS. 2-4, respectively, for example.

The top portion 501 of the timing diagram 500 includes time periods 503a, 503 b, 503 c, and 503 d (shown with a hatched pattern) during whichthe medical device does not deliver an electromagnetic radiation pulseto the treatment area or sends a synchronization pulse to the imagingdevice. The time periods 506 a, 506 b, and 506 c (shown with a whitepattern) illustrate periods of time during which the medical devicedelivers an electromagnetic radiation pulse to the treatment area orsends a synchronization pulse. For example, the time instances 504 a and505 a are associated with the start and end, respectively, of anelectromagnetic radiation pulse delivered to the patient during timeperiod 506 a. A combustion flash can result when the electromagneticradiation delivered to the area of treatment reaches the stone. Thecombustion flash can be received by the imaging device as a large pulseor blast of electromagnetic radiation, for example. A period T_(L)between electromagnetic radiation and/or synchronization pulses isassociated with the frequency of operation (F_(L)) of the medicaldevice.

The bottom portion 502 of the timing diagram 500 illustrates an exampleof the effects of the medical device pulses on the video frames producedby the imaging device. In this example, the imaging device is operatedusing a rolling shutter such that each row in a video frame has anexposure start time (e.g., a row reset) that is offset from the exposurestart time of an adjacent row in the same frame. Moreover, the frequencyof operation of the imaging device (i.e., the frame rate) issubstantially the same as the frequency of operation of the medicaldevice (F_(L)).

FIG. 5A shows a frame A at the start (left) of the bottom portion 502that includes multiple valid rows 510 (shown with a hashed pattern). Avalid row 510 is a row that includes a number of valid pixels above athreshold number, for example, and that has not be prematurelyterminated or corrupted as a result of a frame resetting that occursfrom a synchronization pulse produced by the medical device or fromreceiving electromagnetic radiation associated with the medical device(e.g., a combustion flash) at the imaging device. A valid pixel can be,for example, a pixel that operates properly (e.g., not defective)and./or is not saturated from being exposed to very high levels ofelectromagnetic radiation. The frame A occurs within the time period 503a during which the medical device does not deliver electromagneticradiation to the treatment area or sends a synchronization pulse.

A frame B is shown having its first and second top rows being valid rows510. Both the first and second rows occur within the time period 503 aduring which the medical device does not deliver electromagneticradiation to the treatment area or sends a synchronization pulse. Theend portion of the third row (shown with a dotted pattern) of frame B,however, occurs within the time period 506 a during which the medicaldevice delivers electromagnetic radiation to the treatment area or sendsa synchronization pulse to synchronize the imaging device and themedical device. In this example, the medical device pulse results in aframe reset at the imaging device (i.e., circuitry in the imaging deviceproduces a frame reset) such that frame B is prematurely terminated(i.e., premature end-of-frame) at its third row. The third row of frameB is corrupted by the frame reset that occurs. A corrupt row 514 can bea row that includes a number invalid pixels resulting from a frame resetproduced by a medical device pulse.

The imaging device starts a new frame C following the frame resettingthat occurs as a result of the premature end of frame B. Frame C,however, has as its first rowan invalid row 516 (shown in whitepattern). The first row of frame C starts when the medical deviceproduces a pulse within the time period 506 a. The first valid row 510of frame C is its second row. As was shown with respect to frame B, thethird row of frame C is corrupted by a frame resetting that occurs froma pulse produced by the medical device during the time period 506 b suchthat frame C is prematurely terminated at its third row. FIG. 5A alsoshows a frame D having as its top rowan invalid row 516 that resultsfrom a pulse produced by the medical device during time period 506 c.The remaining rows in frame D, however, are valid rows 510 as they occurwithin the time period 503 d in which the medical device does notdeliver an electromagnetic radiation pulse or sends a synchronizationpulse.

The example described in FIG. 5A illustrates the effects of operatingthe medical device at substantially the same frequency as the frame rateof the imaging device. Multiple video frames, in some instances multipleconsecutive video frames, can be prematurely terminated by the operationof the medical device. The terminated video frames may include few ifany valid rows. In this regard, the quality of the video output can beseverely affected by the effects that the pulses produced by the medicaldevice have on the imaging device. As a result, a medical practitionermay not be able to use the video output produced by the imaging deviceto effectively assist in the performance of a medical procedure (e.g., alithotripsy procedure).

FIG. 5B is a timing diagram 550 illustrating an increased number ofvalid rows when an imaging device is operated at, for example, twice (orhigher) the frequency of operation of a medical device, according to anembodiment. The timing diagram 550 includes a top portion 551 thatillustrates periods when electromagnetic radiation pulses are deliveredor synchronization pulses are sent by a medical device, such as themedical device 124 described above with respect to FIG. 1, for example.The timing diagram 550 includes a bottom portion 552 that illustratesmultiple frames associated with a video output from a given imagingdevice being used in the medical procedure (e.g., a lithotripsyprocedure), such as the imaging devices 228, 238, and 428 describedabove with respect to FIGS. 2-4, respectively, for example. In thisexample, the imaging device operates at a frame rate having a frequencythat is at least twice the frequency of operation the medical device. Insome embodiments, the frame rate can be less than twice the frequency ofthe operation of the medical device (the pulse frequency).

The top portion 551 of the timing diagram 550 includes time periods 553a, 553 b, 553 c, and 553 d (shown with a hatched pattern) during whichthe medical device does not deliver an electromagnetic radiation pulseto the treatment area or sends a synchronization pulse to the imagingdevice. The time periods 556 a, 556 b, and 556 c (shown with a whitepattern) illustrate periods of time during which the medical devicedelivers an electromagnetic radiation pulse to the treatment area orsends a synchronization pulse. For example, the time instances 554 a and555 a are associated with the start and end, respectively, of anelectromagnetic radiation pulse delivered to the patient during timeperiod 556 a. A period T_(L) between electromagnetic radiation and/orsynchronization pulses is associated with the frequency of operation(F_(L)) of the medical device and is substantially the same period asshown in FIG. 5A.

The bottom portion 552 of the timing diagram 550 illustrates an exampleof the effects of increasing the frame rate of the imaging device to afrequency of at least twice the frequency of operation (e.g., energy orpulse frequency) of the medical device. In this example, the imagingdevice is operated using a rolling shutter such that each row in a videoframe has an exposure start time (e.g., a row reset) that is offset fromthe exposure start time of an adjacent row in the same video frame.

FIG. 5B shows a frame A at the start (left) of the bottom portion 552that includes multiple valid rows 560 (shown with a hashed pattern). Theframe A occurs within the time period 553 a during which the medicaldevice does not deliver electromagnetic radiation to the treatment areaor sends a synchronization pulse. A frame B is shown having its top fourrows being valid rows 560. The top four rows of frame B occur within thetime period 553 a during which the medical device does not deliverelectromagnetic radiation to the treatment area or sends asynchronization pulse. The end portion of the fifth row (shown with adotted pattern) of frame B, however, occurs within the time period 556 aduring which the medical device delivers electromagnetic radiation tothe treatment area or sends a synchronization pulse to synchronize theimaging device and the medical device. In this example, the medicaldevice pulse produces a frame reset such that frame B is prematurelyterminated (i.e., premature end-of-frame) at its fifth row. The fifthrow of frame B is corrupted by the frame reset that occurs and is shownas a corrupt row 564.

Because of the higher frame rate of the imaging device, a given videoframe that occurs after the premature end of frame B is likely to havemore valid rows than video frames that occur after a premature end of aframe when the frequency associated with the frame rate of the imagingdevice is substantially the same as the frequency of operation of themedical device. For example, a new frame C follows the frame resettingthat occurs as a result of the premature end of frame B. Frame C,however, has as its top row an invalid row 566 (shown in white pattern)that starts when the medical device produces a pulse within the timeperiod 556 a. Although the top row of frame C is an invalid row 556, theremaining rows of frame C occur during the time period 553 b and arevalid rows 560. Following the last valid row 560 of frame C, a scheduledframe reset occurs and a new frame D starts during the time period 553b. Similar to frame B, the frame D ends prematurely at its fifth rowfrom the top as a result of a pulse produced by the medical deviceduring the time period 556 b. A frame E is shown at the end (right) ofthe bottom portion 552 in which all the rows are valid rows 560.

When the imaging device is operated at twice (or higher) the frequencyof operation of the medical device, it is possible to recover the imageinformation with a small loss of signal-to-noise ratio. For example, inone embodiment, pairs of adjacent (or more than two) video frames (e.g.,frame C and frame D in FIG. 5B) can be added, combined, etc. or at leastthe valid portions of pairs each adjacent video frame can be added,combined, etc. to substantially replicate the behavior of an imagingdevice operating at a lower frequency or frame rate. In anotherembodiment, depending on the amount of latency that may be acceptedthrough the imaging system, more complex temporal filtering operations,such as a sin(x)/x filter, for example, can be used to combine theinformation in valid rows of adjacent video frames while minimizingtemporal aliasing effects. Moreover, the increase in frame rate in theimaging device can reduce the apparent motion artifacts that aretypically produced by a rolling shutter.

In some embodiments, frame processing techniques such as interpolation,extrapolation, frame delays, and/or so forth can be used to define validframes (or portions of valid frames) when the frame rate of the imagingdevice is less than twice the frequency of operation of the medicaldevice. Information associated with one or more frames can be, forexample, interpolated to produce portions of (or entire) valid framesthat will replace portions of (or entire) invalid frames. In someembodiments, the display of the frames (e.g., the valid frames) to anoperator can be delayed (e.g., delayed a few frames) to allow for timeto perform the interpolation. The duration of the delay can be definedso that the delay is substantially imperceptible to, for example, anoperator.

In some embodiments, the imaging device (e.g., imaging sensor) can beconfigured such that a readout operation or process occurs upon the endof a power-on reset (POR) operation, or upon receiving a synchronizationsignal, such as a synchronization pulse from a medical device, forexample. It may be desirable that the duration of the POR operation beshort to guarantee that the internal states of certain components and/orportions of the imaging device are properly set. In some embodiments, atthe end of the POR operation the imaging device can reset each of therows and may not perform a readout operation until after a exposure orintegration operation of the rows has occurred. By instead following thePOR operation with a readout operation and having the reset of rowsoccur after the readout operation, it may be possible to have at leasttwo complete (i.e., not prematurely terminated) video frames read outbetween medical device pulses such that the valid rows in each of thetwo complete video frames can be added or combined to produce a completeand valid video frame that can be presented to a medical practitioner.

As described above, in some instances, the electromagnetic radiationpulses produced by a medical device can result in combustion flashes.The light or flashes that result from the combustion (e.g.,fragmentation) of the stone can saturate pixels in a given imagingdevice. A large number of saturated pixels can result in loss of imageinformation in the video output from the imaging device. In theseinstances, the imaging device need not reset (e.g., frame reset) for theloss of information that results from pixel saturation to affect thequality of the video output.

FIG. 6A is a timing diagram illustrating rows with saturated pixelsresulting from the operation of a medical device (e.g., a lithotriptor),according to an embodiment. The timing diagram 600 includes a topportion 601 that illustrates periods when a combustion flash or otherlike electromagnetic radiation results from a pulse delivered by amedical device, such as the medical device 124 described above withrespect to FIG. 1, for example. The timing diagram 600 includes a bottomportion 602 that illustrates multiple video frames associated with avideo output from a given imaging device being used with the medicaldevice in a medical procedure (e.g., a lithotripsy procedure), such asthe imaging devices 228, 238, and 428 described above with respect toFIGS. 2-4, respectively, for example.

The top portion 601 of the timing diagram 600 includes time periods 603a, 603 b, 603 c, and 603 d (shown with a hatched pattern) during whichthe medical device does not deliver an electromagnetic radiation pulseto the treatment area or sends a synchronization pulse to the imagingdevice. The time periods 606 a, 606 b, and 606 c (shown with a whitepattern) illustrate periods of time during which a combustion flash orother like electromagnetic radiation results from a pulse delivered by amedical device. The combustion flash can be received by the imagingdevice as a large pulse or blast of electromagnetic radiation, forexample. The time instances 604 a and 605 a are associated with thestart and end, respectively, of a combustion flash or light that occursduring time period 606 a. A period T_(L) between flashes is associatedwith the frequency of operation (F_(L)) of the medical device.

The bottom portion 602 of the timing diagram 600 illustrates an exampleof the effects of high levels of electromagnetic radiation (e.g.,flashes) on the video frames produced by the imaging device. In thisexample, the imaging device is operated using a rolling shutter suchthat each row in a video frame has an exposure start time (e.g., a rowreset) that is offset from the exposure start time of an adjacent row inthe same frame. Moreover, the frequency of operation of the imagingdevice (i.e., the frame rate) is substantially the same as the frequencyof operation of the medical device (F_(L)).

FIG. 6A shows a frame A at the start (left) of the bottom portion 602that includes multiple valid rows 610 (shown with a hashed pattern). Avalid row 610 is a row that includes a number of valid pixels above athreshold number, for example. A valid pixel can be, for example, apixel that operates properly (e.g., not defective) and/or is notsaturated from being exposed to very high levels of electromagneticradiation. The frame A occurs within the time period 603 a during whichthe medical device does not deliver electromagnetic radiation to thetreatment area or sends a synchronization pulse.

A frame B is shown having its top three rows being valid rows 610. Thetop three rows of frame B occur within the time period 603 a duringwhich a flash or other like deliver electromagnetic radiation associatedwith the medical device is not received at the imaging device. The endportion of the fourth row (shown with a dotted pattern) of frame B,however, occurs within the time period 606 a during which a very highlevel of electromagnetic radiation is received at the imaging device.The level of electromagnetic radiation is sufficiently high to saturatea large number of pixels in the fourth row of frame B. The fourth row offrame B is corrupted by the saturation of the pixels and is shown as aninvalid row 614. The remaining rows of frame B also occur within thetime period 606 a and are also corrupted by the saturation of pixelsthat results from the high levels of electromagnetic radiation upon theimaging device. The remaining rows of frame B each can include a largenumber of saturated pixels and are shown as invalid rows 616 (shown withwhite pattern). In this embodiment, while the fourth row of frame B isthe first row of frame B corrupted by the high levels of electromagneticradiation upon the imaging device, the imaging device does not reset(i.e., frame B is not prematurely terminated) and the remaining rows offrame B are exposed to the high levels of electromagnetic radiation.

Frames C, D, E, and F in FIG. 6A show the effects of having certain rowsoccur during the periods of high levels of electromagnetic radiationthat can result from the operation of the medical device. For example,frame C includes only two rows that are valid rows 610, frame D includesonly two rows that are valid rows 610, frame E includes only one validrow 610, and frame F includes nine valid rows 610.

The example described in FIG. 6A illustrates the effects of operatingthe medical device at substantially the same frequency as the frame rateof the imaging device. Multiple video frames, in some instances multipleconsecutive video frames, can have a very limited number of valid rowsbecause of the pixel saturation effects produced by the operation of themedical device. In this regard, the quality of the video output can beseverely affected by the effects that the combustion flashes or likeelectromagnetic radiation associated with the operation of the medicaldevice have on the imaging device. As a result, a medical practitionermay not be able to use the video output produced by the imaging deviceto effectively assist in the performance of a medical procedure (e.g., alithotripsy procedure).

FIG. 6B is a timing diagram illustrating an increased number of validrows when an imaging device is operated at is operated, for example, attwice (or higher) the frequency of operation of the medical device,according to an embodiment. The timing diagram 650 includes a topportion 651 that illustrates periods when a combustion flash or otherlike electromagnetic radiation results from a pulse delivered by amedical device, such as the medical device 124 described above withrespect to FIG. 1, for example. The timing diagram 650 includes a bottomportion 652 that illustrates multiple frames associated with a videooutput from a given imaging device being used in the medical procedure(e.g., a lithotripsy procedure), such as the imaging devices 228, 238,and 428 described above with respect to FIGS. 2-4, respectively, forexample. The imaging device operates at a frame rate having a frequencythat is at least twice the frequency of operation the medical device. Insome embodiments, the frame rate can be less than twice the frequency ofthe operation of the medical device.

The top portion 651 of the timing diagram 650 includes time periods 653a, 653 b, 653 c, and 653 d (shown with a hatched pattern) during whichthe medical device does not deliver an electromagnetic radiation pulseto the treatment area or sends a synchronization pulse to the imagingdevice. The time periods 656 a, 656 b, and 656 c (shown with a whitepattern) illustrate periods of time during which a combustion flash orother like electromagnetic radiation results from a pulse delivered by amedical device. For example, the time instances 654 a and 655 a areassociated with the start and end, respectively, of a combustion flashor like electromagnetic radiation that occurs during time period 656 a.A period T_(L) between flashes is associated with the frequency ofoperation (F_(L)) of the medical device and is substantially the sameperiod as shown in FIG. 6A.

The bottom portion 652 of the timing diagram 650 illustrates an exampleof the effects of increasing the frame rate of the imaging device to afrequency of at least twice the frequency of operation (e.g., energy orpulse frequency) of the medical device. In this example, the imagingdevice is operated using a rolling shutter such that each row in a videoframe has an exposure start time (e.g., a row reset) that is offset fromthe exposure start time of an adjacent row in the same video frame.

FIG. 6B shows a frame A at the start (left) of the bottom portion 652 inwhich all its rows are valid rows 660 (shown with a hashed pattern). Theframe A occurs within the time period 653 a during which the medicaldevice does not deliver electromagnetic radiation to the treatment areaor sends a synchronization pulse. A frame B is shown having its topthree rows and its bottom two rows being valid rows 660. The top threerows of frame B occur within the time period 653 a during which a flashor other like deliver electromagnetic radiation associated with themedical device is not received at the imaging device. Similarly, thebottom two rows of frame B occur within the time period 653 b duringwhich a flash or other like deliver electromagnetic radiation associatedwith the medical device is not received at the imaging device. The endportion of the fourth row (shown with a dotted pattern) of frame B,however, occurs within the time period 656 a during which a very highlevel of electromagnetic radiation is received at the imaging device.The level of electromagnetic radiation is sufficiently high to saturatea large number of pixels in the fourth row of frame B. The fourth row offrame B is corrupted by the saturation of the pixels and is shown as aninvalid row 664. The remaining rows of frame B that occur within thetime period 656 a are also corrupted by the saturation of pixels thatresults from the high levels of electromagnetic radiation upon theimaging device and are shown as invalid rows 666 (shown with whitepattern).

In contrast to the frames in FIG. 6B, the frames C, D, E, and F in FIG.6B have a larger number of valid rows as a result of operating theimaging device at a frequency (e.g., frame rate) that is at least twicethe operating frequency of the medical device. For example, frame Cincludes six rows that are valid rows 660, frame D includes six rowsthat are valid rows 660, frame E includes five valid rows 660, and frameF includes nine valid rows 660.

When the imaging device is operated at twice (or higher) the frequencyof operation of the medical device, it is possible to recover the imageinformation with a small loss of signal-to-noise ratio. For example, inone embodiment, adjacent video frames (e.g., frames B, C, and/or D inFIG. 6B) can be added or combined, or at least the valid portions of theadjacent video frames can be added or combined, to substantiallyreplicate the behavior of an imaging device operating at a lowerfrequency or frame rate. In some embodiments, video frames can be addedor combined by adjusting, replacing, and/or modifying rows to produce avideo frame at a frequency (e.g., frame rate) that is lower than thefrequency of the video frames.

FIG. 7 is a system block diagram of a module 700 configured to replaceinvalid rows, according to an embodiment. The module 700 includes a rowvalidation module 720, a selector 730, and a frame buffer module 710. Insome embodiments, the module 700 can include an image data module 705.In other embodiments, the image data module 705 can be separate from themodule 700. In some embodiments, the module 700 can be included in animage processing module such as the image processing modules 220 and 320described above with respect to FIGS. 2 and 3. In other embodiments, themodule 700 can be included in an imaging device configured to havingimage processing capabilities such as the imaging device 420 describedabove with respect to FIG. 4. The components of the module 700 can besoftware-based, or hardware-based and software-based.

The image data module 705 is configured to store video frame informationincluding information associated with one or more rows of a given videoframe. The image data module 705 is configured to produce an output O71that includes information associated with one or more rows from thatvideo frame. The image data module 705 is configured to send the outputO71 to the row validation module 720 and to the selector 730.

The row validation module 720 is configured to receive the output O71from the image data module 705. The row validation module 720 isconfigured to determine whether a received row is valid or invalid. Thevalidity determination can be based on, for example, a number orpercentage of valid pixels in the row, a number or percentage ofsaturated pixels in a row, and/or a validity of an associated row in oneor more video frames related to a time instance before a time instanceof the video frame. For example, the validity determination can be basedon whether an associated row (e.g., a row in the same location) in adifferent frame is valid or invalid. The row validation module 720 isconfigured to produce an output O72 that indicates whether the rowreceived from the image data module 705 is valid or invalid.

The selector 730 is configured to select between the output O71 from theimage data module 705 and an output O74 from the frame buffer module710. The selected output is transferred through the selector 730 to anoutput O73 produced by the selector 730. When the output O71 from therow validation module 720 indicates that the row received from the imagedata module 705 is valid, the selector 730 is configured to select theoutput O71 and transfer the information included in the output O71 tothe output O73. The valid row information in the output O73 is alsostored in the frame buffer module 710. When the output O71 from the rowvalidation module 720 indicates that the row received from the imagedata module 705 is invalid, the selector 730 is configured to select theoutput O74 and transfer the information included in the output O74 tothe output O73. In this regard, the invalid row is replaced with a lastvalid row in the buffer module 710.

The video output produced by a given imaging device can be affected asthe combustion flash that is produced at the stone during a medicalprocedure (e.g., a lithotripsy procedure) can induce a large photocurrent (i.e., optically-generated current) in the imaging device thatcan result in changes to the power supply voltage or on-chip biasvoltage in the imaging device. These changes in supply voltage canaffect the pixel response to electromagnetic radiation (e.g., lightresponse), particularly with respect to a charge or voltage offset(e.g., black level or zero-light level). To compensate or correct forchanges that occur to charge or voltage offsets as a result of supplyvoltage variations, the dark pixels in the imaging device, such as thedark pixels 432 described above with respect to FIG. 4, for example, canbe used to determine temporal offset changes based on measurements madeon different frames at different instances in time.

FIG. 8 is a schematic block diagram of a module 800 configured tocompensate for changes in pixel offset, according to an embodiment. Themodule 800 includes a dark reference pixels module 870, a temporallowpass filter module 880, and an adder 890. In some embodiments, themodule 800 can include an image data module 805. In other embodiments,the image data module 805 can be separate from the module 800. In someembodiments, the module 800 can be included in an image processingmodule such as the image processing modules 220 and 320 described abovewith respect to FIGS. 2 and 3. In other embodiments, the module 800 canbe included in an imaging device configured to having image processingcapabilities such as the imaging device 420 described above with respectto FIG. 4. The components of the module 800 can be software-based orhardware-based and software-based.

The image data module 805 is configured to store video frame informationincluding information associated with one or more rows of a given videoframe. The image data module 805 can include dark pixel informationassociated with the video frame. The image data module 805 is configuredto produce an output O81 that includes information associated with oneor more rows from that video frame and/or dark pixel informationassociated with that video frame. The image data module 805 isconfigured to send the video frame information to the adder 890 and thedark pixel information to the dark reference pixels module 870.

The dark reference pixels module 870 is configured to receive dark pixelinformation associated with one or more rows of a video frame. The darkreference pixels module 870 is configured to collect, organize, and/orprocess the dark pixel information. In some embodiments, the darkreference pixels module 870 can include a buffer (not shown) to storedark pixel information associated with one or more video frames. Thedark reference pixels module 870 is configured to produce an output O82that includes information associated with the dark pixel informationreceived and/or processed by the dark reference pixels module 870.

The temporal lowpass filter module 880 is configured to receive theoutput O82 from the dark reference pixels module 870. The temporallowpass filet module 880 is configured to temporally and/or spatiallyfilter the dark pixel information associated with the video frame or thedark pixel information associated with a video frame at a time beforethe time of the video frame. For example, the filtering that occurs inthe temporal lowpass filet module 880 can be based on dark pixelinformation from a current video frame and/or from one or more previousvideo frames. The filtering provided by the temporal lowpass filtermodule 880 can be used to prevent or reduce normal levels of noise inthe imaging device from disrupting the image in the video output,particularly when large gains are to be applied subsequently to theinformation associated with the video frame. The temporal lowpass filtermodule 880 is configured to produce an output O83 that includes thefiltered dark pixel information. The adder 890 is configured to subtractthe filtered dark pixel in the output O83 from the video frameinformation in the output O81 from the image data module 805. Bysubtracting the filtered dark pixel information from the video frameinformation, the module 800 can compensate for the changes in charge orvoltage offset produced by the imaging device from the variations insupply voltage that result from the combustion flash associated with theoperation of the medical device.

FIG. 9 is a schematic block diagram of a module 900 configured toreplace invalid rows and compensate for changes in pixel offset,according to an embodiment. The module 900 includes a dark referencepixels module 970, a temporal lowpass filter module 980, a fast-settlingfilter module 995, a selector 940, a frame buffer module 910, a flashdetector module 915 (e.g., a lithotripsy flash detector module), aselector 930, and an adder 990. In some embodiments, the module 900 caninclude an image data module 905. In other embodiments, the image datamodule 905 can be separate from the module 900. In some embodiments, themodule 900 can be included in an image processing module such as theimage processing modules 220 and 320 described above with respect toFIGS. 2 and 3. In other embodiments, the module 900 can be included inan imaging device configured to having image processing capabilitiessuch as the imaging device 420 described above with respect to FIG. 4.The components of the module 900 can be software-based or hardware-basedand software-based.

The image data module 905 is configured to store video frame informationincluding information associated with one or more rows of a given videoframe. The image data module 905 can include dark pixel informationassociated with the video frame. The image data module 905 is configuredto produce an output O91 that includes information associated with oneor more rows from that video frame and/or dark pixel informationassociated with that video frame. The image data module 905 isconfigured to send the video frame information in output O91 to theselector 930, the frame buffer module 910, and/or the flash detectormodule 915. The image data module 905 is configured to send dark pixelinformation in output O91 to the dark reference pixels module 970.

The flash detector module 915 is configured to determine when a receivedrow or rows from a video frame are valid or invalid. The flash detectormodule 915 is configured to determine when a flash or likeelectromagnetic radiation occurs associated with the medical devicebased on, for example, the validity of rows from the video frame. Theflash detector module 915 is configured to produce an output O95 thatindicates whether the row received from the image data module 705 isvalid or invalid. The flash detector module 915 is configured to enablethe storage of valid rows on the frame buffer module 910 when a row isdetermined to be a valid row.

The selector 930 is configured to select between the output O91 from theimage data module 905 and an output O97 from the frame buffer module910. The selected output is transferred through the selector 930 to anoutput O96 produced by the selector 930. When the output O91 from theflash detector 915 indicates that the row received from the image datamodule 905 is valid, the selector 930 is configured to select the outputO91 and transfer the information included in the output O91 to theoutput O96. The valid row information in the output O96 is also storedin the frame buffer module 910. When the output O91 from the flashdetector 915 indicates that the row received from the image data module905 is invalid, the selector 930 is configured to select the output O97and transfer the information included in the output O97 to the outputO96. The frame buffer module 910 is configured to include in the outputO96 information associated with a valid row (e.g., a valid row from aprevious frame) that can be used to replace or correct at least aportion of the received row deemed to be invalid by the flash detector915. For example, the invalid row can be replaced with a last valid rowstored in the frame buffer module 910.

The dark reference pixels module 970 and the temporal lowpass filtermodule 980 can be similar to the dark reference pixels module 870 andthe temporal lowpass filter module 880 described above with respect toFIG. 8, respectively. The dark reference pixels module 970 is configuredto produce an output O92 that includes information associated with thedark pixel information received and/or processed by the dark referencepixels module 970. The output O92 is received by the temporal lowpassfilter module 980 and the fast-settling filter module 995. Thefast-settling filter module 995 is configured to temporally and/orspatially filter the dark pixel information associated with the videoframe or the dark pixel information associated with a video frame at atime (e.g., relative time) before the time of the video frame.

The selector 940 is configured to select between the output O93 from thetemporal lowpass filter module 980 and an output O94 from thefast-settling filter module 995. The selected output is transferredthrough the selector 940 to an output O98 produced by the selector 940.When the output O91 from the flash detector 915 indicates that the rowreceived from the image data module 905 is valid, the selector 940 isconfigured to select the output O93 and transfer the informationincluded in the output O93 to the output O98. When the output O91 fromthe flash detector 915 indicates that the row received from the imagedata module 905 is invalid, or that multiple rows received from theimage data module 905 are invalid, the selector 940 is configured toselect the output O94 and transfer the information included in theoutput O94 to the output O98. In this regard, when a predeterminednumber of rows received from the image data module 905 are invalid, itis desirable that the fast-settling filter module 995 be selected. In afast-settling mode, data can be buffered in the frame buffer module 910until a next valid row is received from the image data module 905. Thedark reference pixel information is collected until a sufficiently largeinformation sample is obtained to cancel out or compensate for a largeportion of the noise that is part of individual samples of the darkreference pixel information. The compensated dark reference pixelinformation can be averaged to determine a charge or voltage offset tobe subtracted from the video data information.

The adder 990 is configured to subtract the dark pixel information(e.g., offset information) in the output O98 from the selector 940 fromthe video frame information in the output O96 from the selector O93 toproduce an output O99. By subtracting the dark pixel information fromthe video frame information, the module 900 can compensate for invalidrows and for the changes in charge or voltage offset produced by theimaging device from the variations in supply voltage that result fromthe combustion flash associated with the operation of the medicaldevice.

FIG. 10 is a schematic block diagram of a module 1000 configured tocompensate for changes in pixel offset, according to another embodiment.The module 1000 includes a dark pixel coefficients module 1035, anaverage module 45, a dark reference pixels module 1070, a temporallowpass filter module 80, and adders 1055, 65, and 1090. In someembodiments, the module 1000 can include an image data module 1005and/or the calibration data module 1025. In other embodiments, the imagedata module 1005 and/or the calibration data module 1025 can be separatefrom the module 1000. In some embodiments, the module 100 can beincluded in an image processing module such as the image processingmodules 220 and 320 described above with respect to FIGS. 2 and 3. Inother embodiments, the module 1000 can be included in an imaging deviceconfigured to having image processing capabilities such as the imagingdevice 420 described above with respect to FIG. 4. The components of themodule 1000 can be software-based or hardware-based and software-based.

The image data module 1005, the dark reference pixels module 1070, andthe temporal lowpass filter module 80 are similar to the image datamodule 805, the dark reference pixels module 870, and the temporallowpass filter module 880 described above with respect to FIG. 8. Inthis regard, the output O101 from the image data module 1005 includesinformation associated with one or more rows from that video frameand/or dark pixel information associated with that video frame. Thetemporal lowpass tilter module 80 is configured to produce an outputO103 that that includes filtered dark pixel information.

In this embodiment, an offset for each pixel in a video frame can beindividually corrected or compensated to account for normal variationsin leakage (dark) current and/or other offsets (e.g., source-followerthreshold voltage) that occur across a pixel array as a result of themanufacturing process.

The calibration data module 1025 is configured to store informationassociated with offset correction coefficients of a given imagingdevice. In one example, the offset correction coefficients can include acharge or voltage offset associated with each dark pixel in the array ofthe imaging device obtained or determined during a manufacturing orsystem calibration operation. The calibration data module 1025 isconfigured to produce an output O102 that includes the informationassociated with the offset correction coefficients. The dark referencepixel coefficients module 1035 is configured to process the informationassociated with offset correction coefficients. The average module 1045is configured to average the processed information associated withoffset correction coefficients from the dark reference pixelcoefficients module 1035. The average module 1045 is configured toproduce an output O103 that includes averaged offset correctioncoefficients information.

The adder 1055 is configured to subtract the output O104 from theaverage module 1045 from the output O103 from the temporal lowpassfilter module 1080 to produce an output O105. The adder 65 is configuredto add the output O105 from the adder 1055 and the output O2 from thecalibration data module 1025 to produce an output O6. The adder 1090 isconfigured to subtract the output O106 from the adder 1065 from theoutput O101 from the image data module 1005 to produce an output O107.The output O107 includes video frame information that has been adjustedto compensate for offset differences between calibration conditions andoperating conditions.

FIG. 11 is a flow chart illustrating a method for replacing invalidrows, according to an embodiment. At 1100, a row associated with a givenframe is received from an imaging device (e.g., an image sensor). At1110, the number of saturated pixels in the received row is determined.When the number (or percentage) of saturated pixels is above a firstpredetermined threshold number (or threshold percentage), TH1, theprocess proceeds to 1150 where the received row is determined or deemedto be an invalid row. When the number (or percentage) of saturatedpixels is below or equal to the first predetermined threshold number (orthreshold percentage), TH1, the process proceeds to 1120. In oneexample, a received row can be deemed to be invalid when the percentageof saturated pixels is above 50% of the total number of pixels in therow.

At 1120, when a previous row in the same frame that includes thereceived row is an invalid row and the number (or percentage) ofsaturated pixels in the current row is above a second predeterminedthreshold number (or threshold percentage), TH2, where TH2 is lower thanTH1, then the process proceeds to 1150 where the received row isdetermined or deemed to be an invalid row. Otherwise, the processproceeds to 1130 where the received row is determined or deemed to be avalid row. A prior invalid row can include an immediately prior row thatwas deemed invalid or a row within a predetermined number of prior rowsof the frame that includes the received row that was deemed invalid.After 1130, at 1140, the received row is deemed to be a valid row can bestored in a buffer.

After 1150, at 1160, when the same row as the received row in multipleconsecutive frames (e.g., more than N consecutive frames) has beendeemed to be an invalid row, the process can proceed to 1180 where thereceived row that was deemed to be an invalid row at 1150 is now deemedto be a valid row. Otherwise, the process can proceed to 1170 where thereceived row deemed to be an invalid row is replaced in the frameincluding the received row with a valid row from a frame at a time(e.g., relative time) earlier than the time of the frame that includesthe received row. For example, the valid row to be used to replace thereceived row deemed to be an invalid row can come from the buffer at1140.

The correction operation described with respect to 1160 and 1180 abovecan be used to prevent an area of an image in the video output frombeing static for a substantial period of time (e.g., 100 milliseconds)as a result of consecutive invalid rows in the same location. Such along period of time can make the identification and processing ofinvalid rows more visible to a human observer (e.g., medicalpractitioner) and, sometimes, more objectionable than the artifactssought to be addressed. In one example, when operating at a frame rateof 30 frames-per-second (fps), the number N of consecutive frames in1160 can be set to, for example, three consecutive replacements beforean invalid row is to be deemed valid. The selection of the number (N) ofconsecutive frames in 1160 can depend on various factors, includingapparent latency and/or the likelihood or probability of false ormisclassification of a row as an invalid row.

FIG. 12 is a flow chart illustrating a method for using an imagingdevice proximate to a medical device (e.g., a lithotriptor), accordingto an embodiment. At step 1200, an imaging device, such as the imagingdevices 228, 328, and 428 described above with respect to FIGS. 2-4, isinserted into a patient's body. At 1210, after the inserting at 1200, amedical device, such as the medical device 124 described above withrespect to FIG. 1, for example, is activated to transmit (e.g., emit) anelectromagnetic energy or a synchronization pulse to the patient's body.The imaging device generates multiple frames (e.g., video frames) at aframe frequency of, for example, at least twice a frequency of operation(e.g., energy or pulse frequency) of the medical device. The imagingdevice terminates at least a current frame from the multiple frames inresponse to at least one of a synchronization pulse from the medicaldevice or an electromagnetic energy associated with the medical device.A start or reset time of each row in each frame from the multiple framesis offset from a start or reset time of an adjacent row in that sameframe.

At 1220, a power level of the electromagnetic radiation or energytransmitted (e.g., emitted) to the patient's body from the medicaldevice is adjusted. In one example, the power level is adjusted by amedical practitioner. In another example, the power level is adjusted toa predetermined level by, for example, a medical device such as thecontrol module 210 described above with respect to FIG. 2. At 1230, theframe frequency or frame rate of the multiple frames from the imagingdevice is adjusted. At 1240, a frame from the multiple frames can bedetermined to be a valid frame. In some embodiments, the valid frame canresult from adding or combining valid portions of two or more framesfrom the multiple frames. Multiple valid frames can be generated thatinclude the frame determined to be a valid frame. The multiple validframes have a frame frequency that is lower than the frame frequency ofthe multiple frames.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. For example, the imaging system described herein can includevarious combinations and/or sub-combinations of the components and/orfeatures of the different embodiments described. Embodiments of theimage processing module can be provided without the imaging devicedescribed herein. In other embodiments, components and/or features ofthe image processing module can be included in the imaging device.Although described with reference to use with a medical device andrelated to medical procedures (e.g., lithotripsy procedures), it shouldbe understood that the imaging device and the image processing module,as well as the methods of using the imaging device and the imageprocessing modules can be used in the treatment of other conditions.

Some embodiments may include a processor and a relatedprocessor-readable medium having instructions or computer code thereonfor performing various processor-implemented operations. Such processorsmay be implemented as hardware modules such as embedded microprocessors,microprocessors as part of a computer system, Application-SpecificIntegrated Circuits (“ASICs”), and Programmable Logic Devices (“PLDs”).Such processors may also be implemented as one or more software modulesin programming languages as Java, C++, C, assembly, a hardwaredescription language, or any other suitable programming language.

A processor according to some embodiments may include media and computercode (also can be referred to as code) specially designed andconstructed for the specific purpose or purposes. Examples ofprocessor-readable media include, but are not limited to: magneticstorage media, such as hard disks, floppy disks, and magnetic tape;optical storage media, such as Compact Disc/Digital Video Discs(“CD/DVDs”), Compact Disc-Read Only Memories (“CD-ROMs”), andholographic devices; and magneto-optical storage media, such as opticaldisks and read-only memory (“ROM”) and random-access memory (“RAM”)devices. Examples of computer code include, but are not limited to,micro-code or micro-instructions, machine instructions, such as producedby a compiler, and files containing higher-level instructions that areexecuted by a computer using an interpreter. For example, an embodimentmay be implemented using Java, C++, or other object-oriented programminglanguage and development tools. Additional examples of computer codeinclude, but are not limited to, control signals, encrypted code, andcompressed code.

The many features and advantages of the present disclosure are apparentfrom the detailed specification, and thus, it is intended by theappended claims to cover all such features and advantages of the presentdisclosure which fall within the true spirit and scope of the presentdisclosure. Further, since numerous modifications and variations willreadily occur to those skilled in the art, it is not desired to limitthe present disclosure to the exact construction and operationillustrated and described, and accordingly, all suitable modificationsand equivalents may be resorted to, falling within the scope of thepresent disclosure.

What is claimed is:
 1. An apparatus, comprising: an imager configured togenerate a plurality of frames at a frame frequency greater than anelectromagnetic energy emission pulse frequency of a medical device,each frame of the plurality of frames including a first plurality ofrows; an electronic shutter module configured to offset a start time ofeach row of the first plurality of rows in each frame from the pluralityof frames from a start time of an adjacent row in that same frame; andan image processing module configured to generate a plurality of validframes based on at least a portion of the plurality of frames generatedby the imager, the plurality of valid frames having a frame frequencylower than the frame frequency of the plurality of frames.
 2. Theapparatus of claim 1, wherein the electronic shutter module terminates acurrent frame from the plurality of frames in response to at least oneof a synchronization pulse from the medical device and anelectromagnetic energy associated with the medical device.
 3. Theapparatus of claim 1, wherein the imager is a solid-state imager havingan addressable pixel array including a second plurality of rows, eachrow of the second plurality of rows being associated with a row from thefirst plurality of rows in a frame from the plurality of frames.
 4. Theapparatus of claim 1, wherein a valid portion of a frame from theplurality of frames includes at least one valid row and is included in avalid frame from the plurality of valid frames.
 5. The apparatus ofclaim 1, wherein the image processing module includes a temporal filterconfigured to combine a valid portion of at least two adjacent framesfrom the plurality of frames to produce a valid frame from the pluralityof valid frames.
 6. The apparatus of claim 1, wherein the imager isconfigured to read out an initial frame from the plurality of frames inresponse to at least one of a power-on reset being complete and asynchronization signal from the medical device.
 7. The apparatus ofclaim 1, wherein a first frame from the plurality of frames is before asecond frame from the plurality of frames, and wherein the electronicshutter module is configured to reset to a start of the second frameafter the first frame is terminated in response to at least one of asynchronization pulse from the medical device and an electromagneticenergy associated with the medical device.
 8. The apparatus of claim 1,wherein a valid frame from the plurality of valid frames includes atleast one valid row, the at least one valid row having a number of validpixels above a predetermined threshold number.
 9. The apparatus of claim1, wherein a first frame from the plurality of frames is before a secondframe from the plurality of frames, and wherein the image processingmodule is configured to replace an invalid portion of the second framewith an associated valid portion from the first frame.
 10. The apparatusof claim 1, wherein the image processing module includes a bufferconfigured to store a valid portion of at least one frame from theplurality of frames.
 11. The apparatus of claim 1, wherein the imageprocessing module is configured to adjust an illumination valueassociated with a pixel in a valid frame from the plurality of validframes based on at least one of a dark reference pixel informationreceived from the imager and a calibration information stored in theimage processing module.
 12. The apparatus of claim 1, wherein the imageprocessing module includes a temporal low-pass filter module configuredto produce an output based on a dark reference pixel informationreceived from the imager, and wherein the image processing module isconfigured to adjust an illumination value associated with a pixel in avalid frame from the plurality of valid frames based on the output fromthe temporal low-pass filter.
 13. The apparatus of claim 1, wherein theimage processing module includes a fast-settling filter moduleconfigured to produce an output based on a dark reference pixelinformation received from the imager, wherein the fast-settling filtermodule is actuated in response to at least one of a synchronizationpulse from the medical device and an electromagnetic energy associatedwith the medical device, and wherein the image processing module isconfigured to adjust an illumination value associated with a pixel in avalid frame from the plurality of valid frames based on the output fromthe fast-settling filter.
 14. The apparatus of claim 1, wherein theapparatus includes an endoscope.
 15. A method, comprising: generating aplurality of video frames with an imager, the plurality of video framesincluding at least a first video frame and a second video frame;determining whether a row in a video frame from the plurality of videoframes is an invalid row in response to receiving electromagneticenergy; replacing at least one invalid row in the second video framewith an associated valid row from the first video frame to produce avalid video frame; and generating a plurality of valid video frames, theplurality of valid video frames having a frame frequency lower than aframe frequency of the plurality of video frames generated by theimager.
 16. The method of claim 15, further comprising generating theplurality of video frames at a first frequency, the first frequencybeing greater than an electromagnetic energy emission pulse frequency ofa medical device.
 17. The method of claim 15, wherein a row in thesecond video frame is invalid when an associated row in the first videoframe is invalid and a number of valid pixels in the row in the secondvideo frame is below a predetermined threshold number.
 18. The method ofclaim 15, further comprising deeming an invalid row to be a valid rowafter the invalid row has been replaced in a predetermined number ofconsecutive video frames from the plurality of video frames.
 19. Amethod, comprising: inserting an imager into a body of a patient;activating a medical device to transmit an electromagnetic energy to thebody of the patient; generating a plurality of frames at a framefrequency greater than an electromagnetic energy emission pulsefrequency of the medical device, wherein the imager is configured toterminate at least a frame from the plurality of frames in response toat least one of a synchronization pulse from the medical device and anelectromagnetic energy associated with the medical device; andoffsetting a start time of each row in each frame from the plurality offrames from a start time of an adjacent row in that same frame.
 20. Themethod of claim 19, further comprising: adjusting a power level of theelectromagnetic energy transmitted to the body of the patient from themedical device; adjusting the frame frequency of the plurality offrames; determining whether a frame from the plurality of frames is afirst valid frame; and generating a plurality of valid frames includingthe first valid frame, the plurality of valid frames having a framefrequency lower than a frame frequency of the plurality of frames.